Enzymes are products made from raw materials such as animals, plants, and fungi through microbial fermentation, containing specific bioactive components. They contain multiple nutrients such as amino acids, vitamins, organic acids, crude polysaccharides, and bioenzymes. Traditional Chinese fermented foods like douchi (fermented black soybeans), pickles, and fermented tofu are also considered enzyme-rich foods.

Compared to directly consuming fruits and vegetables, enzymes not only retain the nutritional value of the original substances but also produce some small molecule nutrients beneficial to human health, which are more easily absorbed and utilized by the body. They are favored by researchers both domestically and internationally and are a highly regarded category in the field of functional foods.